Regulating system



June 1, 1937. H. "r. LANGABEER REGULATING SYSTEM Filed Oct. 20, 1934 6Sheets-Sheet l INVENTOR By H.7I LANG/{BEER A T TORNEV June 1, 1937.

H. T. LANGABEER REGULAT ING SYSTEM Filed Oct. 20, 1954 6 Sheets-Sheet- 2INVENTOR H.7.' LANGABEER TTORNEY June 1937. H. T. LANGABEER REGULATINGSYSTEM Filed Oct. 20, 1954 e Sheets-Sheet s m Qbx mQm QDM

-//v1 /v TOR H. 7. LANGABEER A T TORNE V June 1, 1937. LANGABEER2,082,110 Q REGULATING SYSTEM Filed Oct. 20, 1934 S SheetS-Sheet 4 LINVENTOR H LANG/l BEER A T TORNE Y REGULATING SYSTEM Filed Oct. 20, 19346 Sheets-Sheet 5 luHl' INVENTOR H. 7?. LANGABEER ATTORNEY June 1, 1937.H. 'r. LANGABEER 2,082,110

REGULATING SYSTEM F Filed Oct. 20, 1934 6 Sheets-Sheet 6 INVENTI'OR h.7'. LANGABEER ATTORNEY Patented June 1 1937 UNITED STATES PATENT OFFICEREGULATING SYSTEM New York Application October 20, 1934, Serial No.749,153

8 Claims.

This invention relates to automatic regulating systems for electricgenerators used in connection with a floating storage battery, and moreparticularly to systems for controlling the connections of a pluralityof generators to the load circuit of the system, one at a time, inaccordance with the requirements of the load.

The principal object of the invention is to secure reliable automaticcontrol of systems of the above mentioned character.

Another object is to automatically start and stop motor-generator setsas required in accordance with the load requirements and the voltage ofthe battery.

Another object is to prevent simultaneous starting of two or moregenerator sets upon the return of the power supply following a powerfailure.

Another object is to disconnect any one of the motor-generator sets fromservice at will and to transfer the automatic control of that set to thenext set.

A still further object is to automatically regulate the voltage of eachgenerator, supplying the load, within predetermined high and low limitsand to prevent overloading of the generators under low battery voltageconditions.

Another object is to insure that all generators connected to the load,except the last operating generator of the group, shall at all timesdeliver their individual predetermined full load current output,

Another object is to stop a newly started generator if the batteryvoltage rises above a certain value before the generator is connected tothe-load and remains above this value for a predetermined time interval.

Another object is to regulate the battery voltage between predeterminedhigh and low voltage limits during the period the battery is floatingacross the load and between other predetermined high and low voltagelimits during the period the battery is receiving a charge.

Another object is to stop any generator, in the event of the opening ofan associated individual fuse, and automatically start the next idlegenerator and connect it to the load in substitution for the disabledgenerator.

Another object is to stop all machinery when l the fuse in the commonlead between the generator and battery is opened.

Features of this invention whereby the foregoing objects are attainedare as follows:

One feature of the invention resides in an arrangement whereby thestarting of the next idle generator of the group to relieve an overloadcondition on the generators in operation is jointly controlled by anammeter relay in the output of the last operating generator and avoltmeter relay connected across the battery, whereby even though thelast operating machine of the group supplying the load has reached itsfull load capacity and its current relay has closed its high contactthis will not be eifective to start the next machine if the batteryvoltage is above a predetermined value. In other words the lastoperating machine must be running at full load and the battery voltagemust be below a predetermined value before the next machine is startedand connected to the load.

Another feature of the invention resides in the use of alarm fuses inthe various circuits of each generator, any one of which when blown willclose a circuit to start the next idle machine in the group and stop thegenerator associated with the operated fuse.

Another feature resides in the use of an alarm fuse in the common ormain lead between the generators and the battery whereby when this fuseopens all generators in operation will stop.

A still further feature resides in an arrangement whereby if a generatorwhich had been supplying the load is manually disconnected from thebattery and load for maintenance or other reasons and a succeedingmachine is substituted therefor, the stopped machine will not berestarted, when it is switched back ready for service, and thesubstitute machine stopped, if the load is stationary or decreasing.

A related feature resides in means whereby if the load is increasingwhen the stopped enerator is switched back ready for service, it willstart and gradually take up the load previously carried by itssubstitute generator to a point where the current output of thesubstitute generator has been reduced below zero at which time thesubstitute generator will stop,

Another feature of the invention resides in the provision of anarrangement whereby upon the resumption of the power supply following afailure thereof the normal periodic control of the individual generatorfield rheostats is disabled and they are successively moved by acontinuous operation to rapidly bring their associated generators up tofull output. When the battery voltage rises to a proper value the normalrheostat control is again made effective.

Additional features of the invention will appear from consideration ofthe following description:

This invention will be more readily understood by reference to thedrawings, which show one embodiment of the invention, in which Fig. '7shows the arrangement of Figs. 1, 2, 3, 4, 5, and 6 to form a completeoperative system. Four motor-generator sets are shown together withsuitable control apparatus so arranged that the current delivered by themotor-generator sets is controlled by the voltage of the battery, thecurrent being increased when the battery voltage becomes lower than aspecified value and decreased when the battery voltage rises above thatvalue. If the voltage of the battery becomes such that the regulatedmotor-generator set delivers its full load current, anothermotor-generator set is started and connected to the load and thefluctuations in the load are taken up by this machine up to its fullload capacity. In a similar manner if the battery voltage rises sufficiently to cause the last connected motor-generator to reduce itsoutput until it takes current from the battery, the motor-generatordisconnects itself from the load and the control is shifted to theprevious machine. In order that the control mechanism may not be subjectto constant wear due to battery voltage fluctuations of short duration,arrangements are provided so that the battery voltage is tested and thecurrent adjusted at intervals of say ten seconds.

The invention will now be described in detail with reference to thedrawings. It will be assumed that no generators are running, thatswitches II4, I30, M4, and 430 are closed and that the battery voltageis below the specified minimum in which case generator I shown as I04 onthe drawings is started and connected to the battery. This isaccomplished by the operation of relay I02. The operating circuit forrelay I02 is traced from ground through the right-hand contact andarmature of relay 504, right-hand normally made contacts ofout-of-service key II9, the winding of relay I02 to battery through theright-hand back contact of test key I20 and the left-hand back contactof relay 20I. Relay I02, operated, connects the power supply to motorstarter WI. The path for the operation of motor starter IOI is tracedfrom power supply conductor I35, through the winding of motor starterIOI through circuit breaker contacts I42, through the contacts of relayI02 to power supply conductor I39. Motor starter IOI connects powersupply conductors I35, I38 and I39 to motor I03 which is mechanicallycoupled to generator I04. Relay 203 also operates in a path traced frombattery through the left-hand back contact of relay 20I, outer normallymade contacts of contactor III to ground through the winding of relay203. Relay 203, operated, connects ground through its right-hand frontcontact, through the filament of generator failure lamp I05, through theright-hand back contacts of test key I20 to battery through theleft-hand back contact of relay 20I. Generator failure lamp I05 lightsin this circuit and remains lighted until contactor III operates andreleases relay 203. Relay 203 also connects ground through its left-handfront contacts to alarm relay 529. The latter relay is of the slowoperating type and operates and lights alarm lamp 530 only in casegenerator I04, or one of the other generators fails to be connected tothe load within a predetermined time which is less than the operatingtime of relay 529.

During the stopped and starting period of generator I04, the fieldrheostats I34 and 2I5 are short-circuited so that the voltage will buildup rapidly. When this voltage reaches a sufliciently high value relay30l operates. The field circuit of generator I04 previous to theoperation of relay SM is traced from the negative generator terminal,back contacts of relay 30I to the positive generator terminal throughthe field winding I33. After the operation of relay 30I, the fieldcircuit includes manually controlled rheostat I34 and motor-driven'-.rheostat 2I5. Under this condition the field circuit is traced fromthe negative terminal of generator I04, motor rheostat 2I5, manualrheostat I34 to the positive terminal of generator I04 through fieldwinding I33. The operating path for relay 30! is traced from groundthrough the winding of relay 30I, the negative terminal of generatorI04, the positive terminal of generator I04 to the grounded terminal ofbattery 60I through fuse MI and ammeter relay H1. The voltage fromgenerator I04 also operates relay 300 in a path traced from groundthrough the winding of relay 306, through the left-hand inner contactsof test key I20, fuse II5, the negative terminal of generator I 04, thepositive terminal of generator I04 to ground through fuse MI and ammeterrelay II'I.

Since it has been assumed that the battery voltage is below thespecified minimum, the low voltage contacts of voltmeter relay BIS willbe closed and relay 6I6 operated each time motor interrupter 210 closesits contacts. The voltmeter relay circuit is traced from ground throughthe winding of voltmeter relay 6I5, variable resistance 6I8 to batterythrough the contacts or ll.

key 0| I. The circuit for the operation of relay 6E0 is traced fromground through the winding of relay GIG, low voltage contacts ofvoltmeter relay 6I5, to battery through the contacts of motorinterrupter 2I0. Interrupter 2 I0 is driven by motor 209 at a speed tocause it to close its con tacts at definite intervals, say for one-halfsec- 0nd every ten seconds. Each time relay BIG operates it connectsbattery through its contacts, through the right-hand back contact of keyIi I3, the left-hand back contacts of relays B00, 604, and 305, theright-hand front contact of relay 305, back contact of relay 303, theback contact of key I22, through the limit contacts of limit switch 2 I6of motor-driven rheostat 2I5, through the winding of relay 2I3 to groundthrough the inner back contacts of relay 2I9. Relay 2I3 operates in thiscircuit and connects battery to motor 2I4 causing it to rotate in adirection to reduce the resistance of rheostat 2I5, which is in thefield circuit and to raise the voltage 01 generator I04. The circuit forthe operation or motor 2 I4 is traced from ground through the innerfront contacts of relay 2I3, armature cl motor 2I4, outer back contactsof relay 2I9, to battery through fuse I I6. The field winding 2I8associated with armature 2I4 is excited continuously in a circuit tracedfrom ground through field winding 2 I 8 to battery through fuse I I6.

As explained previously motor 2I4 will cut out resistance in the fieldcircuit of generator I04 and raise its voltage whenever interrupter 2I0makes it contacts, while voltmeter relay 6I5 is on its low voltagecontacts.

When the generator voltage rises to a value,

fuse 620, switch H4, the right-hand winding of relay H2, the winding ofrelay H3, the negative terminal of generator I04, the positive terminalof generator I04 to ground through fuse MI and ammeter relay II1. RelayH3 being polarized does not operate when the generator voltage is lowerthan the battery voltage.

The operation of relay I I3 causes the operation of relay I I2 in acircuit traced from the negative terminal of generator I04, contacts ofrelay II3, the left-hand winding of relay H2 to the positive terminal ofgenerator I04. The operation of relay H2 causes the operation ofcontactor III in a circuit traced from the positive terminal ofgenerator I04, the contacts of relay H2, the winding of contactor III,the middle back contacts of contactor III to the negative terminal ofgenerator I04. After the operation of contactor III the winding of relayH3 is shortcircuited, relay I I3 is released and the circuit for holdingcontactor III operated is traced from the negative terminal of generatorI 04, resistance I40, the winding of contactor II I, the contacts ofrelay I I2 to the positive terminal of generator I04. The operation ofcontactor III connects generator I04 to battery 00L This circuit istraced from the positive terminal of generator I04, fuse I lI, ammeterrelay II1 to the grounded side of battery SM and from the negative terminal of generator I04, inner front contacts of contactor III, right-handwinding of relay H2, switch H4 to the ungrounded terminal of battery 60Ithrough fuse 620. Since the generator voltage is higher than the batteryvoltage current flows from the generator to the battery and thence tothe load and this current is in a direction to hold relay H2 operated.The release of relay I I3 also alters the circuit for the left-handwinding of relay H2 to include resistance I02. Under this conditionrelay H2 is held operated for the most part by the current through itsright-hand winding in order to insure the release of this relay shouldthe generator draw current from the battery. The circuit for theleft-hand winding of relay I I2 when contactor II I operates is tracedfrom the positive terminal of generator I04, left-hand winding of relayI I2, resistance I62 to the negative terminal of generator I04. Theoperation of contactor III also opens the operating circuit of relay 203which releases, extinguishing generator failure lamp I05, and openingthe circuit to relay 529.

Increasing load As the load on the battery increases the battery voltagewill be decreased and voltmeter relay 6 I5 will close its low voltagecontacts and operate relay ISIS whenever interrupter 2I0 closes itscontacts, as described previously. Relay 6I0, operated, causes theoperation of relay 2I3 which closes the circuit to armature 2 I4 andreduces the resistance in the field circuit of generator I04. Reducingthe field resistance causes generator I04 to increase its output voltageand more current flows to the battery to compensate for the greaterload.

Decreasing load When the voltage of battery 00I rises due to a decreasein the load, voltmeter relay 6I5 closes its high voltage contacts andrelay H1 is operated as often as interrupter 2I0 closes its contacts.The circuit for the operation of relay (H1 is traced from batterythrough the contacts of interrupter 2I0, armature and high voltagecontacts of voltmeter relay 6 I 5 to ground through the winding of relay6I1. The operation of relay IiI1 causes the operation of relay 2I9 in acircuit traced from battery through the contacts of relay IiI1,left-hand back contacts of key BI3, right-hand back contacts of relays609, 604, and 305, the left-hand outer back contact of test key I20, theback contact of key I2I, the contacts of limit switch 2" to groundthrough the winding of relay 2I9 and the inner back contacts of relay2I3. Relay 2I9, operated, completes a circuit to the armature 2I4 ofmotor-driven rheostat H5 and causes it to increase the resistance in thefield circuit of generator I04. The circuit involving armature 2I4 istraced from ground through the inner front contact of relay 2I9,armature 2I4 to battery through the outer back contact of relay 2I3 andfuse H6. Relay 6I1 continues to operate under control of interrupter 2I0 and cause motor rheostat 2I5 to increase the field resistance andlower the generator voltage as long as voltmeter relay 6 I 5 remains onits high voltage contacts or until the motor has cut all the resistanceof rheostat 2I5 into the field circuit of generator I04 and has operatedlimit contacts 2I1, thus opening the circuit to relay 2I0 and stoppingmotor 2I4.

Starting and connection of additional generator If the load on thebattery increases and the battery voltage is correspondingly lowered andmotor-driven rheostat 2I5 increases the output of generator I04 up to apredetermined value, which may be the full load of the generator,ammeter relay H1 closes its contacts. The closure of the contacts ofammetcr relay H1 starts the second generator, shown on the drawings asgenerator I09, raises its voltage to a value above the battery voltageand connects it to the battery in the following manner: The closure ofthe contacts of ammeter relay I I1 operates relay 303 by connectingground to its upper winding terminal, its lower terminal being connectedto battery. The operation of relay 303 opens the circuit from relay BIGto relay 2I3, previously described and prevents motor rheostat 2 I5 fromfurther increasing the load of generator I04. If voltmeter relay 6I5remains on its low voltage contacts, relay 6 I 6 will be operated andrelay 5I0 is energized in a circuit traced from battery through thecontacts of relay 6I0, right-hand back contacts of key 6I3 to groundthrough the winding of relay 5I0. Relay 5 I0, operated, completes acircuit from ground on the contacts of arnmeter relay H1 left-hand backcontact of relay 204, right-hand outer front contact of relay 5|0 tobattery through the righthand' back contact and winding of relay 221,operating the later relay. Relay 221 looks in a circuit traced fromground through the front contacts of power failure relay 208, which isheld operated by the power supply and releases only under the conditionof power failure, through the back contact of relay 201 and theright-hand front contact and winding of relay 221 to battery. Theoperation of relay 221 causes the operation of relay I01 in a circuittraced from bat' tery through the left-hand front contacts of relay 221,right-hand back contact of relay 204, right-hand outer back contact oftest key I25, winding of relay I01, right-hand back contact of key I26,right-hand inner back contact of relay 205 to ground through theright-hand back contact of relay 504. Relay 206 also operates in acircuit traced from battery through the left-hand front contacts ofrelay 221, right-hand as in the case of generator I04.

1 that previously described. Generator back contact of relay 204, outerback contacts of contactor I21 to ground through the winding of relay206. Relay 206, operated, grounds the lead to the alarm relay 529 andlights the generator failure lamp H0 in a manner similar to thatdescribed for the starting of generator I04. The operation of relay I01causes the operation of motor starter I06 which in turn causes motor I08to rotate and generator I09 to build up a voltage The field rheostats ofgenerator I09 are short-circuited by relay 302 in a similar manner tothat described for the starting of generator I04 and when generator I09builds up a suflicient voltage relay 302 operates, removing theshort-circuit from the field rheostats I31 and 22I. Relays-301 and 305also operate on the generator voltage in a circuit traced from groundthrough the windings of relays 301 and 305 in parallel, left-hand innerback contact of test key I25, fuse I32, negative terminal of generatorI09, positive terminal of generator I09 to ground through fuse I43 andammeter relay H8. The operation of relays 301 and 305 shifts the controlcircuit from generator I to generator 2. If the voltage relay remains onits low voltage contacts the voltage of generator I09 is raised by theoperation of motor rheostat 22I in a similar manner to that describedfor generator I. When the voltage of generator I09 rises to a highervalue than that of the battery, relay I29 operates and operates relayI28 and contactor I21. The operation of contactor I21 opens the circuitof relay 206 and connects generator I09 to the load in a manner similarto I04 is maintained at full load and the fluctuations of load are takenup by generator I09 through motor-driven rheostat 22 I.

In a similar manner, generator set 3 is started and connected to thebattery if ammeter relay I I0 closes its contacts due to generator I09having reached a predetermined current output and generator I09 ismaintained at this current and the control is shifted to generator 404.Should generator 404 reach its full load output, generator set 4 isstarted and connected to the battery in the same way and the controlfrom voltmeter relay GIS is shifted to motor-driven rheostat 52I.

Disconnection of generator from battery If more than one generating setis in operation and due to a reduction in the load on the battery, thebattery voltage rises to such a degree that the automatic control of thelast connected generator reduces the output of that generator until itstarts to take current from the battery, this last connected generatoris stopped and the automatic control is shifted to the generator nextpreviously connected.

For example, let it be assumed that generator set I being maintained atfull. load and that generator set 2 is also in operation, its currentoutput being controlled by voltmeter relay 6I5 through motor rheostat22I. If, due to the high voltage condition of the battery, motorrheostat 22I reduces the current output of generator I09 to such adegree that ammeter relay II8 closes its low contacts, current relay 201operated in a path traced from ground on the low current contacts ofammeter relay IIB, left-hand back contacts of relay 206, winding ofrelay 201 to battery through the lefthand front contacts of relay 221.The operation of relay 201 opens the locking path of relay 221,releasing it. Relay 221. released, releases relay 201 and relay I01which in turn releases motor starter I06, disconnecting the power supplyfrom motor I08. Under this condition, generator I09 operates as a motortaking current from the battery. The current in the right-hand windingof relay I 28 is thus reversed and relay I28 released, releasingcontactor I21. Relays 305 and 301 release since generator I09 is nolonger generating a voltage. The release of relay 305 shifts thevoltmeter relay control to motor rheostat 2I5 and relay 301, released,contacts battery through its right-hand outer back contact, theleft-hand outer back contact of key I25, back contact of key I24, thecontacts of limit switch 225, to ground through the winding of relay 226and the inner back contacts of relay 220. Relay 226, operated, operatesmotor 222 to cut in resistance in the field circuit of generator I09.Motor 222 continues to cut in resistance until limit switch 225 isreached which, when operated, opens the circuit to relay 226 whichreleases, stopping motor 222 and leaving motor rheostat in the allresistance cut in position.

Removing a generating set from service If it is desired to remove agenerating set from service for maintenance purposes or for otherreasons, the out of service key H9, I26, M9 or 425 associated with thegenerating set which it is desired to remove, is operated. If, forexample, it is desired to remove generating set 2, key I26 is operated.The operation of this key opens the operating circuit of relay I01releasing it, if generator I09 is operating at that time, and in turnreleasing motor starter I06. Relay I28 and contactor I21 release onreverse current as previous ly described. The operation of key I26 alsocauses the operation of relays 204 and 308 in a circuit traced fromground through the right-hand back contacts of relay 504, right-handinner back contact of relay 205, right-hand front contact of key I26 tobattery through the windings of relays 204 and 308 in, parallel. Relay204, operated, transfers the conductor attached to the high currentcontacts of ammeter relay II1 from relay 221, to relay 509 so thatgenerator set 3 will be started when ammeter relay II1 closes itscontacts and the voltmeter relay (SI 5 is on its low voltage contacts.

Restoring a generating set to service For the purpose of describing therestoring of a generator to service it will be assumed that the load issuch as to require the operation of two generators and that key I26 hasbeen previously operated, removing generator set 2 from service. Underthis condition, generator I04 will be supplying its full load with thecontacts of ammeter relay II1 closed and generator 404 will be inoperation with a variable load under control of voltmeter relay 6I5.

Restoring key I26 to its normal position opens the operating path andreleases relays 204 and 308. Relay 204, released, closes a circuit fromground through the contacts of ammeter relay Il1, left-hand back contactof relay 204, righthand outer front contact of relay 5I0, which isoperated when voltmeter relay 6I5 closes its low voltage contacts, tobattery through the righthand back contacts and winding of relay 221.

Relay 221 looks and causes motor I09 to be connected to the power supplyand generator I 09 to build up its voltage as previously described.Relays 305 and 301 operate on the generator voltage as before andwhenever interrupter 2I0 Ill! closes its contacts, a circuit iscompleted from battery through the contacts of interrupter 2I0,right-hand outer front contact of relay 605, back contact of relay 606,left-hand front contact of relay 301, back contact of relay 304, backcontact of key I23, the contacts of limit switch 224 to ground throughthe winding of relay 220 and inner back contact of relay 226.

Relay 220 operates in the circuit traced above and causes motor-drivenrheostat 22I to cut out resistance in the field circuit of generatorI09..

The voltage of generator I09 is thereby raised and when it reaches avalue higher than that of the battery relay I29 operates, operatingrelay I28 and contactor I21 and connecting generator I09 to the battery.Relay 220 continues to be operated whenever interrupter 2 I0 closes itscontacts and as the voltage of generator 509 is raised, the batteryvoltage will be raised and motor rheostat 5| 5 will gradually reduce theoutput of generator 404 as that of generator I09 is increased untilammeter relay 4I1 closes its low current contacts and. disconnectsgenerator 404 from the battery as previously described. When generator404 is disconnected the control from voltmeter relay (H5 is shifted tomotor rheostat 22I through the release of relays 604 and 605.

Operation of generator set which is disconnected from service Let it beassumed that it is desired to operate generating set 2 which has beenremoved from service by the operation of the out-of-service key I26, fortesting or for other reasons. Key I25 is provided for this purposewhich, when operated, opens the operating circuit of relays 305 and 301to prevent shifting the automatic voltage control to this generating setwhen the generator builds up a voltage and opens the circuit from therighthand back contact of relay 301 to relay 225 so that motor rheostat2I5 will not automatically cut in all of its resistance when relay 301is released. Relays 204 and 308 are also operated so that the contactsof ammeter relay II1 will cause generator set 3 to be started shouldgenerator set I become fully loaded. The operating path for relays 204and 308 is traced from ground through the right-hand back contacts ofrelay 504, right-hand inner back contact of relay 205, right-hand innerfront contacts of key I25 to battery through the windings of relays 204and 308 in parallel. Switch I30 is opened to disconnect the generatingset from the battery.

Generator set 2 may now be started and stopped by means of key I26 inthe manner described previously and any tests made which may bedesirable. The voltage of generator I09 may be raised by operating keyI23 or lowered by the operation of key I24. The circuit involving keyI23 is traced from battery through fuse I3 I, front contact of key I23,limit switch contacts 224 to ground through the winding of relay 220 andthe inner back contact of relay 226. The circuit involving key I24 istraced from battery through fuse I3I, front contact of key I24, limitswitch contacts 225 to ground through the winding of relay 226 and theinner back contact of relay 220. Relay 220 operated, causes motorrheostat 22I to cut resistance out of the field circuit of generatorIlls and the operation of relay 225 causes rheostat 22I to cutresistance into the field circuit.

When it is desired to restore generator set 2 to service key I26 isoperated to the out-of-service position, test key I25 is; restored tonormal and switch I30 closed. Key I26 is then restored to normal,restoring generator set 2 to normal automatic operation as describedunder Restoring a generator set to service.

Power failure In the event of a failure of the power supplied overconductors I35, I38, and I39, the generators which are operating at thetime will operate as motors, draw reverse current from the battery andcause the release of their reverse current relays such as relay I I2 andcontactors such as contactor III, which are associated with generator I.The failure of the power also releases relay 208 whose winding isbridged across power supply conductors I38 and I39. The release of relay208 opens the locking circuit to relays 221, 509, and 5I I, releasingany of these relays which may be operated due to the associatedgenerating set being in operation at that time. By releasing theserelays the load is applied gradually after a power failure when relay208 reoperates upon the return of the power supply. Generator I isstarted and connected to the load and the other generators in orderdepending on the load as previously described. In order to prevent thegenerators being returned to the load with their motor rheostats in theposition they happened to be at the time of power failure, normalcircuits from the back contacts of relay 301, 605, and 6I0 are providedto return the rheostats to their maximum resistance cut in positions, aspreviously described.

Constant voltage charge If, because of the failure of voltmeter relayrelay 6I5 or for any other reason it is desired to manually control thecharging or floating rate, key 6I3 is operated which disconnects thecontacts of relays [M6 and EH from the control circult and substituteskeys BIZ and GM. Under this condition the operation of key 6I2 causesthe motor rheostat which is connected to the control circuit at thattime to cut in resistance in the generator field circuit and lower thegenerator voltage. In a similar manner the operation of key 6| 4 causesthe attached motor rheostat to cut resistance out of the generator fieldcircuit associated with it and raise the generator voltage.

Fuse failure The fuses shown on the drawing are of the alarm giving orgrasshopper type. Should the main charging fuse, shown at 620 on thedrawings, fail, the charging circuit will be opened and spring 622 willpull down member 623 into contact with terminal 62I, thereby connectingbattery through members 623 and terminal 62I to ground through thewinding of relay 504, operating this relay. Relay 504, operated, opensthe operating circuits for relays I02, I01, 402, and 401, releasing anyof them which may be operated and disconnecting the associated motorsfrom the power supply by releasing whichever of motor starters IOI, I06,

MI, and 406 that may be operated at the time failure occurs. Theoperation of relay 504 also places ground through its left-hand innerfront contact, through the winding of relay 528 to battery, operatingrelay 528 and lighting lamp 530 as an alarm signal.

If any one of the individual generator fuses I4I, I43, 435 or 438operates, ground is connected to terminals I40, I40, 430 or 440 and theassoelated relay 202, 205, 502 or 505 is operated, disconnecting thegenerating set from the load. For example, let it be assumed thatgenerating sets I and 2 are in operation and that the fuse I43associated with generator 2 operates. After fuse I43 opens the chargingcircuit, member I51 is pulled down by spring I5I into contact withterminal I40, completing a circuit from ground through ammeter relayII8, member I51, terminal I49, through the left-hand winding of relay205 to battery operating relay 205. Relay 205 looks in a circuit tracedfrom ground through the left-hand back contacts of key I25 to batterythrough the right-hand winding and right-hand outer front contacts ofrelay 205. Relay 205, operated, opens the circuit to relay I01,releasing this relay and stopping motor I08; operates relays 204 and 308in a circuit traced from ground through the right-hand back contacts ofrelay 504, right-hand inner front contact of relay 205 to batterythrough the windings of relays 204 and 308 in parallel and operatesalarm relay 521 in a circuit traced from battery through the left-handfront contacts of relay 205 to ground through the winding of relay 521.The operation of relay 204 transfers the contact of ammeter relay II1from the winding of relay 221 to the winding of relay 509, startinggenerator 3, if the contacts of ammeter relay II1 are closed and if thevoltage of the battery is low, causing the operation of relay 5l0. Relay521, operated, lights lamp 530 as an alarm signal. The way in whichgenerator 3 is started,

y connected to the load and the control shifted,

has been previously described.

Should any of the fuses H5, H6, I3I, I32, H5, H6, 43I or 432, associatedwith control circuit operate, the motor-generator set associated withthe operated fuse will be stopped and the succeeding generator setstarted and connected to the load. For example, if generators I and 2are in operation and fuse I3I, associated with the control circuit ofgenerator 2 operates, member IBI is pulled down by spring I55 intocontact with terminal I41 and a circuit is completed from batterythrough member I6I, terminal I41, right-hand outer back contact andright-hand winding of relay 205 to ground through the lefthand backcontact of key I26. Relay 205 operates in this circuit, locks andoperates relay 204, stopping generator 2 and starting generator 3 aspreviously described.

What is claimed, is:

1. In a regulating system, a load circuit, a storage battery associatedtherewith, a first generator connected across said battery and supplying current to said battery and load circuit, a second generator, andcontrol means jointly responsive to a predetermined battery voltage anda predetermined current output of said, first generator independent ofthe output of the battery to cause said second generator to start and beconnected to the battery in parallel with the first generator.

2. In a regulating system. a load circuit, a storage battery associatedtherewith, a first generator connected across said battery and supplyingcurrent to said battery and load circuit, a second generator, andcontrol means responsive to predetermined current output of said firstgenerator independent of the output of the battery to cause said secondgenerator to start and be connected to the battery and load in parallelwith the first generator, and voltage responsive means associated withthe battery adapted to disable said control means until the batteryvoltage is reduced to a predetermined value.

3. In an electric generating system, a load circuit, a storage batteryassociated therewith, a first generator connected across said batteryand supplying current to said battery and load circuit, a plurality ofother generators adapted to be started and connected across said batteryin parallel with said first generator, and means individual to thesecond and each of the succeeding other generators jointly responsive toa predetermined battery voltage and a predetermined current output ofthe preceding generator to start the respective generators in successionand cause their connection to the load circuit.

4. In an electric generating system, a load circuit, a storage batteryassociated therewith, a first generator connected across said batteryand supplying current to said battery and load circuit, a secondgenerator, control means jointly responsive to a predetermined batteryvoltage and a predetermined current output of said first generator tocause said second generator to start, and means responsive to apredetermined higher battery voltage for a predetermined time intervalbefore said second generator is connected to the battery and load tostop said second generator.

5. In an electric generating system, a load circuit, a storage batteryassociated therewith, a first generator connected across said batteryand supplying current to said battery and load circuit, a secondgenerator, manually operated switching means adapted to stop said firstgenerator and cause said second generator to start and be connected tothe battery and load circuit in substitution for the first generator,and means jointly responsive to restoration of said manual switchingmeans and an increasing load to restart said first machine and cause itto assume the load of the second machine.

6. In an electric generating system, a load circuit, a storage batteryassociated therewith, a first generator connected across said batteryand supplying current thereto and to the load circuit, a secondgenerator, an alarm fuse individual to and associated with said firstgenerator, and means responsive to the disruption of said fuse to stopsaid first generator and cause its disconnection from the battery and tostart said second generator and cause its connection to the battery tosupply current thereto in substitution for said first generator.

7. In an electric generating system, a load circuit, a storage batteryassociated therewith, a plurality of generators adapted to besuccessively started and connected in parallel across said battery andsupply current thereto and to the load circuit in accordance with thecurrent requirements of the load circuit, a common conductor betweensaid generators and battery, an alarm fuse in circuit therewith, andmeans responsive to the disruption of said fuse to stop all generatorsin operation.

8. In an electric generating system, a load cirsuit, a storage batteryassociated therewith, a plurality of generators adapted to besuccessively started and connected in parallel across said battery andload circuit to supply current thereto in accordance with the currentrequirements of the load circuit, automatic voltage regulating meansassociated with each generator, a source of current for operating saidregulating means,

means responsive to a predetermined voltage of the storage battery forconnecting said source to said regulating means, means for periodicallyinterrupting said current source, a source of power for operating saidgenerators, and means responsive to the failure of said power source andits subsequent resumption to disable said interrupting means.

HARVEY T. LANGABEER.

